#!/usr/bin/env python3

val1 = input()

if int(val1) >= 30:
    print("Yes")
else:
    print("No") val1 = input() val1 input() input if int(val1) >= 30:
    print("Yes")
else:
    print("No") int(val1) >= 30 int(val1) int val1 30 print("Yes") print "Yes" print("No") print "No" val1 = input() input() val1
#!/usr/bin/env python3

val1 = input()

if int(val1) >= 30:
    print("Yes")
else:
    print("No")